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Related papers: Regge calculus from a new angle

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We consider the purely gravitational fourth-order (in the spacetime curvature) quantum corrections to the Einstein-Hilbert gravity action, coming from superstrings in the leading order with respect to the Regge slope parameter, and study…

High Energy Physics - Theory · Physics 2008-11-26 M. Iihoshi , S. V. Ketov

We demonstrate a tensor renormalization group (TRG) calculation for a two-dimensional Lorentzian model of quantum Regge calculus (QRC). This model is expressed in terms of a tensor network by discretizing the continuous edge lengths of…

High Energy Physics - Theory · Physics 2022-11-24 Yoshiyasu Ito , Daisuke Kadoh , Yuki Sato

We present numerical relativity simulations of cosmological scenarios in which the universe is smoothed and flattened by undergoing a phase of slow contraction and test their sensitivity to a wide range of initial conditions. Our numerical…

General Relativity and Quantum Cosmology · Physics 2020-08-14 Anna Ijjas , William G. Cook , Frans Pretorius , Paul J. Steinhardt , Elliot Y. Davies

We study the Quantum Regge Calculus of Einstein-Cartan theory to describe quantum dynamics of Euclidean space-time discretized as a 4-simplices complex. Tetrad field e_\mu(x) and spin-connection field \omega_\mu(x) are assigned to each…

High Energy Physics - Theory · Physics 2009-12-14 She-Sheng Xue

Is there an approach to quantum gravity which is conceptually simple, relies on very few fundamental physical principles and ingredients, emphasizes geometric (as opposed to algebraic) properties, comes with a definite numerical…

General Relativity and Quantum Cosmology · Physics 2008-11-26 R. Loll

Discretization of general relativity is a promising route towards quantum gravity. Discrete geometries have a finite number of degrees of freedom and can mimic aspects of quantum geometry. However, selection of the correct discrete freedoms…

General Relativity and Quantum Cosmology · Physics 2018-02-28 Seth K. Asante , Bianca Dittrich , Hal M. Haggard

We use the mathematical framework of loop quantum gravity (LQG) to study the quantization of three dimensional (Riemannian) gravity with positive cosmological constant (Lambda>0). We show that the usual regularization techniques (successful…

General Relativity and Quantum Cosmology · Physics 2014-11-20 Alejandro Perez , Daniele Pranzetti

A new method for nonperturbative investigations of quantum gravity is presented in which the simplicial path integral is approximated by the partition function of a spin system. This facilitates analytical and numerical computations…

High Energy Physics - Lattice · Physics 2009-10-28 W. Beirl , P. Homolka , B. Krishnan , H. Markum , J. Riedler

Based on the principle of relativity and the postulate of invariant speed and length, we propose the theory of special relativity with cosmological constant ${\cal SR}_{c,R}$ if the invariant length whose square is the inverse of the…

High Energy Physics - Theory · Physics 2009-11-10 Han-Ying Guo , Chao-Guang Huang , Zhan Xu , Bin Zhou

We study the average number of simplices $N'(r)$ at geodesic distance $r$ in the dynamical triangulation model of euclidean quantum gravity in four dimensions. We use $N'(r)$ to explore definitions of curvature and of effective global…

High Energy Physics - Lattice · Physics 2009-10-22 Bas V. de Bakker , Jan Smit

With toy modelling of conceptual aspects of quantum cosmology and the problem of time in quantum gravity in mind, I study the classical and quantum dynamics of the pure-shape (i.e. scale-free) triangle formed by 3 particles in 2-d. I do so…

General Relativity and Quantum Cosmology · Physics 2011-04-22 Edward Anderson

In this paper we consider a static and regular fluid generating a locally spherically symmetric and time-independent space-time and calculate the leading quantum corrections to the metric to first order in curvature. Starting from a…

High Energy Physics - Theory · Physics 2020-07-13 Xavier Calmet , Roberto Casadio , Folkert Kuipers

Geodesic deviation is the most basic manifestation of the influence of gravitational fields on matter. We investigate geodesic deviation within the framework of Regge calculus, and compare the results with the continuous formulation of…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Sukanya Chakrabarti , Adrian P. Gentle , Arkady Kheyfets , Warner A. Miller

The closed Friedmann--Lema\^itre--Robertson--Walker (FLRW) universe of Einstein gravity with positive cosmological constant in three dimensions is investigated by using the Collins--Williams formalism in Regge calculus. A spherical Cauchy…

General Relativity and Quantum Cosmology · Physics 2021-10-26 Ren Tsuda , Takanori Fujiwara

We provide detailed evidence for the claim that nonperturbative quantum gravity, defined through state sums of causal triangulated geometries, possesses a large-scale limit in which the dimension of spacetime is four and the dynamics of the…

High Energy Physics - Theory · Physics 2010-04-06 J. Ambjorn , J. Jurkiewicz , R. Loll

Unimodular gravity is based on a modification of the usual Einstein-Hilbert action that allows one to recover general relativity with a dynamical cosmological constant. It also has the interesting property of providing, as the momentum…

General Relativity and Quantum Cosmology · Physics 2014-11-21 Dah-Wei Chiou , Marc Geiller

We study modified gravity theory known as Regge-Teitelboim approach, in which the gravity is represented by dynamics of a surface isometrically embedded in a flat bulk. We obtain some particular solutions of Regge-Teitelboim equations…

General Relativity and Quantum Cosmology · Physics 2023-04-12 A. A. Sheykin , A. A. Grechko

The method of four-dimensional Causal Dynamical Triangulations provides a background-independent definition of the sum over geometries in quantum gravity, in the presence of a positive cosmological constant. We present the evidence…

High Energy Physics - Theory · Physics 2007-05-23 J. Ambjorn , J. Jurkiewicz , R. Loll

The discretized closed Friedmann-Lema\^itre-Robertson-Walker (FLRW) universe with positive cosmological constant is investigated by Regge calculus. According to the Collins-Williams formalism, a hyperspherical Cauchy surface is replaced…

General Relativity and Quantum Cosmology · Physics 2021-10-25 Ren Tsuda , Takanori Fujiwara

The space-time length R between a moving source and the observation point is calculated in order to substitute with it the spatial distance D, normally used in the Newton's law of gravitation, as well as in any inverse-square-law.…

General Physics · Physics 2016-09-21 Giuseppina Modestino
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